North Korea may be making a fortune from bitcoin mania

Speculators aren't the only ones cheering the runaway bitcoin boom -- North Korean leader Kim Jong Un may also be celebrating a windfall.

In recent months, experts and officials say North Korea has been "mining" bitcoin, demanding it as ransom payment and outright stealing the digital currency.

"It is a fact that North Korea has been attacking virtualcurrency exchanges," said Lee Dong-geun, a director with South Korea's state-run Korea Internet and Security Agency. "We don't know how much North Korea has stolen so far, but we do know that the police have confirmed the regime's hacking attempts."

It has also proved popular in the past with criminals because of the amount of anonymity it allows. Bitcoin isn't tied to any central bank, and payments can be made anonymously without using banks as middlemen.

That could help North Korea convert its stash into money it can more easily use.

Bitcoins are often held in accounts with online exchanges. But Boland points out that hackers can easily swap them into more obscure cryptocurrencies, move them to other exchanges and eventually withdraw them in traditional currencies like dollars.

"They could do those transactions very quickly ... and avoid traceability of the cash," Boland said.

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North Korea has repeatedly denied involvement in international hacking attacks. But it has made no secret of its interest in bitcoin and other cryptocurrencies.

Last month, the Pyongyang University of Science and Technology touted a lecture from a bitcoin expert who came to North Korea to teach students about the technology behind the digital currency. The university is a high-profile institution where scions of the North Korean elite study.

"Many excellent technical questions were asked about the inner working of bitcoin, its risks, and the measures taken to ensure security," the university said.